In the context of oxidative coloring of hair, the problem arises that irritation of the scalp and damage to the keratinic fibers can occur as a result of the aggressive agents. In particular, the natural hydrophobicity of the keratinic fibers is reduced because the coloring agents resp. lightening agents must first make the hair capable of penetration in order to exert their effect. The water-repellent effect on the one hand, however, provides natural protection for the hair; on the other hand, parameters desired by the consumer, such as shine, softness, suppleness, and the “drape” of the hair, are closely linked to it.
In order to overcome the aforesaid disadvantages, so-called pretreatment agents that are intended to protect the hair from aggressive influence are on the market. These often make the hair heavy, however, or negatively affect the outcome of the lightening resp. coloring of the hair that takes place subsequently; in particular, the washing fastness of the color can be degraded by the pretreatment agent.
The object of the present invention was to make available a method for oxidative hair coloring, with a hair-protecting pretreatment, that overcomes the aforesaid disadvantages without counteracting the success of a subsequent oxidative coloring treatment. The intention was in particular to make available a method in which the hair is not made heavier, and in which the desired effect can also be achieved in the context of a pretreatment not occurring immediately prior to the oxidative coloring treatment, with the result that the time span between pretreatment and coloring can be extended.
The use of aminated silicones in hair care is established art. They are widely used in shampoos and in particular in conditioners in order to exert care-providing effects therein. EP 1771144 B1, for example, discloses hair-conditioning agents having aminofunctional silicones. The agents described therein are post-treatment agents.
European patents EP 1312334 B1 (aminosilicone and thickener) and EP 1312335 B1 (aminosilicone and conditioner) also disclose hair post-treatment agents. Extremely water-rich formulations are also disclosed in the former document.